Laptops come in all sizes ranging from the small netbooks to the large 19 inch machines. What kind of laptop bag you get depends a lot on the size of your laptop. If you are using a large laptop then you will have to go for a larger backpack while smaller ones cannot be adequately protected in a large backpack.
Depending on the size of laptop backpacks, you can either store some extra items in the bag or not. For example a large bag will probably come with extra compartments to carry along one set of clothes for emergency purposes along with some extra space for taking along a notebook.
Reading laptop backpack reviews online is a great way of deciding which carrying case will be the best one for you to buy. There is currently a very large range of makes and models available, many of them at reasonable prices.
The backpacks for smaller laptops are limited by their size and can only accommodate a laptop and some accessories at most. Therefore, not only does the size of your laptop decide the size of the backpack but also what extra space you get from it.
